Community Forums

Ljwt330 · 07-19-2021, 10:47 AM

Quote:

Originally Posted by Terry W

I picked my new unit up yesterday, thanks Bill and Jim.

I think Jim has a good idea about putting the new unit in service and holding onto the existing one as a spare.

One suggestion I would make is to install the new untried unit in the front position. I don't know about the 34' and 36' but the rear is actually easier to change on the 40', all done from the wheel well. The studs/bolts on the front unit are a challenge by yourself until you get them reversed/replaced. Replacing is well worth the effort and nice to do it at your leisure.

My thinking on using the new unit on the front is that when my old one failed it affected headlights, driver fans, gauges and a couple of other things I can't recall. Mine wasn't a total failure it was a reboot situation, all that stuff would go off for maybe 10 seconds at the most and then come back on, no harm no foul. I drove many miles like this on a trip, in the daylight.

When I swapped the unit to the rear it would act the same way, but, the big issue there was that it would shut the engine off and it would have to be restarted, it didn't just come back on. If that happened you would be dead in the water for however long it took to restart, if it did!! Could be a big deal on the freeway.

In the meantime you would have no power assist for your steering, your brakes may or may not work on the hydro boost and brake light, taillights and turn signals probably affected. Not sure if it would affect the trans??

This could happen with any unit, but at least I know my existing unit is working as it should and hasn't let me down. It's a known quantity.

I will install mine in the front and will do the same with my brothers and hopefully all will be well.

Just a thought, Terry

Thanks for all your help Terry, and thanks for the above insight.

I originally thought of installing the new unit in the rear due to ease of access of the bolts, as well as easy reach to the chassis cut off switch. As you can see, my coach also has the rear unit bolts easier to remove than on the front. Your input has me leaning toward a front installation now. As with you, both of mine have not let me down and are known quantities. Though the odds of a new unit failing are small, it is still an unknown and, like you, I'd much prefer to avoid an unexpected engine shut down rather than some cockpit malfunctions.

Jim Durley · 07-19-2021, 01:22 PM

Larry,

Terry's has a 2005 Alpine, I have seen somewhere that the 2004 m.y. has a different process that may require cables that Eng. Mike has. I had planned on getting help from Eng. Mike to program mine during DRR rally in Jan.2022.

Jim D
2004 Alpine MDTS

Ljwt330 · 07-19-2021, 03:21 PM

Quote:

Originally Posted by Jim Durley

Larry,

Terry's has a 2005 Alpine, I have seen somewhere that the 2004 m.y. has a different process that may require cables that Eng. Mike has. I had planned on getting help from Eng. Mike to program mine during DRR rally in Jan.2022.

Jim D
2004 Alpine MDTS

I remember reading through Engineer Mike's posts about the Vansco, and also remember his mentioning of additional cables or "pig-tail." However, I remember that in the context of trying to reprogram a used unit using the two good units. I could be wrong though. 2004 clearly has a different program, but I don't remember an issue with actual programming because he didn't have a 2004 to test.

I haven't made any attempts yet, so if you find out something early, please post. Meanwhile, I'll continue to look.

I just read the manual for the 2820, and it describes all units are able to be programmed in a plug-and-play situation as described by the instructions we've seen. It made clear that this enables replacement of faulty units "in the field."

Jim Durley · 07-19-2021, 06:39 PM

Larry,
I think you are right, it was for reprogrammed VMM's. The 2004 m.y. programming is different from the 2005 m.y. and up. So we do need a 2004 club in case one of us has both units go out. That write up was dated 8/4/16, it would be good to hear from Eng Mike for any updates. I did order two VMM's but have not received a shipping notice yet.
Jim D
2004 Alpine MDTS

whalepirot · 07-20-2021, 05:11 PM

Quote:

Originally Posted by Ljwt330

I remember reading through Engineer Mike's posts about the Vansco, and also remember his mentioning of additional cables or "pig-tail." However, I remember that in the context of trying to reprogram a used unit using the two good units.

I believe you're right, as that post spoke of a 'standoff' between two dissimilarly programmed units.

I've not run the coach with the new unit; just tested it as best I could while stored. I just added the mod and new unit install to my To Do list... That may improve my sometimes sluggish high beam switching.

Maryfaith Moon · 07-23-2021, 11:58 AM

Recapping to confirm my understanding:
1) VMM 2820 units are interchangeable front to rear
2) A new unit need only be programmed in one location (front, in my case) meaning that only steps 1 thru 9 need be completed.

Question:
If one thinks there may be intermittent glitches in an existing unit (as were described above regarding headlight anomalies, etc) is there any danger that hose would be reproduced in the programming of a new VMM?

Ljwt330 · 07-23-2021, 12:33 PM

Quote:

Originally Posted by Maryfaith Moon

Recapping to confirm my understanding:
1) VMM 2820 units are interchangeable front to rear
2) A new unit need only be programmed in one location (front, in my case) meaning that only steps 1 thru 9 need be completed.

Question:
If one thinks there may be intermittent glitches in an existing unit (as were described above regarding headlight anomalies, etc) is there any danger that hose would be reproduced in the programming of a new VMM?

I have some questions about your question.

Are you suggesting to use a unit that has known faults to program a new, unprogrammed unit? Why would one choose to do that?

Intermittent glitches are the bane of all diagnostics. Typically, if there is an issue with a VMM, you switch units, front and rear, to see if the glitch follows the unit. If it does, then that unit should be replaced.

So I guess what you are asking about is if one unit is clearly faulty and needs replacement, and the other has intermittent issues. If that's the case, there's not much risk in trying to program the new unit with the intermittent one as you have no alternative, save find a different coach with two know working units and have them do the programming for you. If your coach is a 2004, choices for the latter option are few.

Terry W · 07-23-2021, 12:48 PM

To tag onto Larry's post my question would be is there something that leads you to believe you have a unit with a glitch or were you just throwing that out there out of curiosity.

Terry

Kid Gloves · 07-23-2021, 01:32 PM

You want to program a unit with one that is known, or believed, to be functioning properly.

If you swap front to back and the problem follows the unit, the problem is with the unit. If the problem stays at the original location, the problem lies elsewhere.

I can only guess at an answer to your question. The 2 guesses would be that the unit would fail to program or the unit would accept a defective program.

whalepirot · 07-24-2021, 08:54 AM

Quote:

Originally Posted by Maryfaith Moon

Recapping to confirm my understanding:
1) VMM 2820 units are interchangeable front to rear

Yes

Quote:

Originally Posted by Maryfaith Moon

2) A new unit need only be programmed in one location (front, in my case) meaning that only steps 1 thru 9 need be completed.

Yes

Quote:

Originally Posted by Maryfaith Moon

an intermittent glitch in an existing unit (as were described above regarding headlight anomalies, etc) is there any danger that hose would be reproduced in the programming of a new VMM?

IMO, that's unlikely as intermittent problems, indeed a "bane", may indicate a hardware problem, not software. That hardware may be outside (downstream) from the VMM output. This is a perfect opportunity to swap units first, to identify the intermittent causal component; via the cited troubleshooting. Understand that a VMM's output failure won't present itself identically, i.e., if the R headlight fails to light, swapping the F unit to the rear will not manifest as R headlight problem, as the VMM's 'failed' output controls a different (downstream) activity when installed aft.

Software gets corrupted (ref: WinDoze) but in my experience, electronic components fail at a higher rate.

Cinequip · 07-24-2021, 11:25 AM

Quote:

Originally Posted by Maryfaith Moon

Question:
If one thinks there may be intermittent glitches in an existing unit (as were described above regarding headlight anomalies, etc) is there any danger that hose would be reproduced in the programming of a new VMM?

If you are having intermittent issues, then swap the units front to back. If you now have different intermittent issues (at the opposite end of the coach as before), then pull that end and program the new unit to the known good one.

whalepirot · 08-15-2021, 03:58 PM

Not easy to see the 'outside' nuts, one hidden behind the large 12v feed and lug. The pic is a weak attempt to 'finger' that one. None were super tight; a small ViseGrip was my helper.

I STRONGLY SUGGEST shutting OFF all 3 connect switches in the battery compartment for two reasons: 1) required for unplugging the VMM and 2) NOT shorting that big 12v lug with a tool, hardware helper's finger.

HD had only one bolt the right size, threaded full-length. Stock bolts are hardened, but don't seem to carry much weight or be under any stress, I bought 4 standard 1/4"/20 of 4" length. I considered lopping off 1/4"or so, but the panel cover installed w/o doing that. I used Loctite blue on the new bolt/nuts to ensure no loosening.

Testing the new unit before finalizing things, I was concerned that the L front directional didn't work and outputs 11, 12 and 13 were flashing; unlike my initial test (above). I followed the post-Step 9 reprograming, to no avail, but slapping the directional itself corrected all problems!

Jim A · 08-15-2021, 07:24 PM

Thanks for the size/length of the bolts. Sounds like a trip to McFadden-Dale hardware coming up!

whalepirot · 08-15-2021, 08:48 PM

Welcome. I knew others would want that info before starting.

1/4" is a bit sloppy in the holes, particularly the VMM's. A 5/16" might fit but I don't see the need and that 'slop' is handy in sliding the unit over all bolts.

The firewall is steel and WRV didn't use flange bolts. I was surprised to see hardened bolts and given my solid mount using std bolts, I still don't think hardened is called for.

Maybe some materials guy will chime in.